Is it ok to put a layer of drywall over an existing layer of drywall?
Answers:
You can put drywall over the existing, however, I wouldn't recommend it. Cost wise it isn't going to save you all that much. Tearing out the existing gives you the opportunity to inspect the wiring, insulation, and framing above it. It also keeps your light openings at the proper depth and keeps you from adding extra weight to our ceiling. I have remodeled a few houses and have been tempted to just cover the existing ceiling, usually cracked plaster; but I always wound up tearing it out and was glad I took the extra step. So the short answer is, yes you can but I wouldn't recommend it. Plastic off the room, open the outside widows, grab a sledge hammer and have a demo party.
Other answers:
no, you have to tear it out. I think it's a building code. Check with your town hall because you're going to have to get it inspected anyway.
no, you have to tear it out. I think it's a building code. Check with your town hall because you're going to have to get it inspected anyway.
Yes, you can put new over old as long as the old is not water damaged (i.e., mildewed).
Also, the old may contain asbestos, so tearing it out might be a very expensive undertaking.
I did in an old 1850 house, but I used 3/8 in drywall, and had the ceiling joists braced for the additional weight. No problems in the 20 yrs it has been there. also put 3/8 in on some walls, over plaster and lath. The other walls I totally tore out, and put new drywall.
No, you have to take the old out.